1. Field of the Invention
This invention relates to disk drive suspensions and, more particularly, to a new design of lifter for the load beam in a disk drive suspension. The lifter is mounted to the load beam rigid portion near the distal end of the load beam. As mounted, the lifter is laterally offset, i.e. offtrack from the load beam centerline, and also vertically offset from the plane of the load beam rigid portion. The invention lifter thus provides a high clearance from the disk for insertion of the camming ramp and a locus of ramp contact with the lifter that is nearer to the disk edge. Moreover, the present lifter is of simple shape readily formed by conventional manufacturing processes.
2. Related Art
A lifter is a part of the suspension mechanism that works with the camming surface of a load ramp to load and unload the slider carried by a flexure-load beam combination from the rotating disk.
In removable disk drives mechanisms are provided to lift the suspensions including a ramp and a cam follower to enable retrieval of the disk (media) without the slider contacting the disk. When the slider is lifted-off the disk, it does not read or write to the disk. Improved disk technology has made disks smoother to avoid stiction problems. Typical lifters used in present drives are hypodermic needle-sized tubes that are glued to the load beam, or attached thereto by crimping tabs or other metal folding structure. These lifters are located either along the centerline of the suspensions or off the centerline of the suspensions. To prevent unwanted read-write activity of the slider, the slider is desirably lifted off the disk as far as possible at the outer diameter of the disk and this is problematical with a centerline-mounted lifter. See FIG. 5 PRIOR ART. A further problem with centerline lifters is the difficulty of lifting the slider by a ramp when the lifter is at the centerline of the long axis of the suspension. There is very little clearance between the disk and the ramp surface. An off-center, or off-track lifter avoids these centerline lifter problems by allowing the suspension to be lifted off relatively closer to the outer diameter of the disk.
It is accordingly an object of the invention to provide a load beam having a lifter structure comprising a lift arm offset vertically and laterally from the load beam centerline a controlled amount to have a predetermined clearance above the disk for optimum insertion of the lifting cam, the clearance being adjustable by variation of the angle and length of the lift arm supporting web. It is a further object to provide a lifter structure that is readily manufactured by conventional techniques, achieving its positioning by a series of linear shifts rather than compound and complex curvatures.
These and other objects of the invention to become apparent hereinafter, are realized in a front end-liftable disk drive suspension load beam adapted for carrying a flexure supporting a slider in operating proximity to a disk, the load beam having a distal end comprising a rigid portion extended in a plane along a longitudinal axis for attachment of the flexure, a lift arm attached to the load beam rigid portion by a web, the web being so dimensioned and angled relative to the load beam rigid portion plane as to attach the lift arm spaced from the load beam rigid portion in rigid portion centerline laterally and vertically offset relation.
In this and like embodiments, typically, the lift arm is extended along a longitudinal axis, the lift arm longitudinal axis being generally parallel with the load beam rigid portion longitudinal axis, the angle of the web to the rigid portion plane is between 1 and 90xc2x0 C., the web comprises a longitudinally extended member fixed at one end to the rigid portion and carrying the lifter arm at its opposite end, the web being reversely turned adjacent the lifter arm, or the web comprises a longitudinally extended member fixed at one end to the rigid portion and carrying the lifter arm at its opposite end, the web being reversely turned adjacent the lifter arm, the web being integral with the lifter arm and separate from the load beam rigid portion, or the web comprises an axially elongated member separately formed from the rigid portion, the web having a base parallel to the rigid portion, an angled portion extending from the base at an angle thereto, a reversely turned portion having an inner edge attached to the angled portion and an outer edge generally parallel to the rigid portion longitudinal axis, a trough between the inner and outer edges, and a terminal portion defining the lifter arm, the lifter arm being generally parallel with the rigid portion longitudinal axis.
In a further embodiment, the invention comprises a front end-liftable disk drive suspension load beam adapted for carrying a flexure supporting a slider in operating proximity to a disk, the load beam having a distal end comprising a rigid portion extended in a plane along a longitudinal axis for attachment of the flexure, a lift arm attached to the load beam rigid portion by a web, the web comprising an axially elongated member separately formed from the rigid portion, the web having a base parallel to the rigid portion, an angled portion extending from the base at an angle thereto between 1 and 90xc2x0 C., a reversely turned portion having an inner edge attached to the angled portion and an outer edge generally parallel to the rigid portion longitudinal axis, a trough between the inner and outer edges, and a terminal portion defining the lifter arm, the lifter arm being generally parallel with the rigid portion longitudinal axis whereby the lift arm is spaced from the load beam rigid portion in rigid portion centerline laterally and vertically offset relation.
In a particularly preferred embodiment, the invention comprises a front end-liftable disk drive suspension load beam having a lifter arm vertically and laterally offset from the load beam centerline, the load beam comprising an elongated member having on a centerline a load beam rigid portion adapted for carrying a slider in operating proximity to a disk, the load beam extending in a plane including the centerline; a lifter structure comprising an elongated lifter arm offset from the load beam centerline and spaced from the load beam a predetermined height, the lifter arm being adapted to engage a lift cam in load beam separating relation from the disk, and a web bracket extending between the load beam and the lifter element, the having a given length greater than the predetermined height, the lifter bracket extending from the load beam at a predetermined angle, the web having a proximate end attached to the load beam rigid portion at the angle, a reversely turned web portion outward of the web proximate end that reduces the effective length of the web to equal the predetermined height, and a distal end terminating the reversely turned portion and attached to the lifter arm, whereby the lifter element is supported at the terminus of the web reversely turned portion to be spaced from the load beam a distance less than the web given length and in offset relation to the load beam centerline.
In this and like embodiments, typically, the web has a width extending in the direction of the load beam elongation that is less than the longitudinal extent of the load beam rigid portion, the lifter structure is elongated and extends beyond the load beam in web-cantilevered relation, the lifter structure is longitudinally dished in stiffening relation, the web predetermined angle is between 1 and 90xc2x0 C. degrees to the load beam plane, the web reverse turned portion comprises parallel web portions, the location of the lifter structure relative to the load beam is variable in manufacturing by varying in concert the predetermined angle of the lifter bracket web to the load beam plane and the reversely turned web portion to obtain the desired location, the lift bracket web has a width extending in the direction of the load beam elongation that is less than the longitudinal extent of the load beam rigid portion, the lifter structure is elongated and extends beyond the load beam in web-cantilevered relation, and/or the lifter structure is longitudinally dished to have an upwardly open-shaped cross-section in lifter structure stiffening relation.